The present invention relates to an image forming apparatus having an electrophotographic system which is used for a printer, etc.
This type of image forming apparatus includes a unit for forming an image in an apparatus main body. The unit has a rotational photosensitive member which is surrounded by a charging device, an exposing device, a developing device, a transcribing device and a fixing device. Then, the charging device electrifies the photosensitive member. The exposing device exposes the photosensitive member, and forms an electrostatic latent image. Developing the electrostatic latent image by the developing device, a toner image is formed on the photosensitive member. The toner image is transferred by the transcribing device onto a recording paper. The fixing device fixes the toner image transferred onto the recording paper.
The apparatus main body includes a register roller mechanism which may have a pair of rollers for conveying a recording paper stocked in a cassette between the photosensitive member and the transcribing device, and output rollers for outputting the recording paper, which has been through out the fixing device, to the outside of the apparatus main body. A conveying path for conveying a recording paper and recording an image thereon is constituted within the apparatus main body.
In the image forming apparatus, while the recording paper is conveyed through the conveying path within the apparatus main body, the movement of the recording paper is stopped for various causes, and the recording paper may be jammed in the conveying path.
For this reason, an opening portion facing to the conveying path is formed in the apparatus main body, and a cover is provided for covering/uncovering opening portion. The parts which surround the conveying path are separately placed on the main body side and on the cover side. Normally, the cover is closed to seal the conveying path. When the recording paper has been jammed, the cover is opened to expose the conveying path, and the parts which surround the conveying path are separated the apparatus main body side and the cover side. Thus, it is easy to take out the recording paper which is jammed in the conveying path.
There are image forming apparatuses known in the prior-art, wherein a photosensitive member is provided in an apparatus main body, a fixing device and a transcribing device are provided on a cover, and one of a pair of register rollers is provided on the cover. Such apparatuses are disclosed in Jpn. Pat. Appln. KOKAI Publication No. 63-244059 and Jpn. Pat. Appln. KOKAI Publication No. 6-266172.
In this structure, however, when the cover is opened, the transcribing device is also moved away from the photosensitive member. Consequently, it is difficult to place the transcribing device at a suitable position relative to the photosensitive member when the cover has been closed, and the transcribing device may not be in a suitable position. Therefore, an image on the photosensitive member may not be transferred on the recording paper in good condition.
Furthermore, as the paired register rollers are separated at the apparatus body side and the cover side, when the cover is closed to contact the paired register rollers with each other, the contact pressure may be unequal in the longitudinal direction of the register rollers, and parallelism may not be maintained. Then, the recording paper may not be conveyed with a suitable position related to the photosensitive member.
Hence, the conventional structure cannot record an image on the recording paper in good condition, and the image quality is deteriorated.
The present invention aims at providing an image forming apparatus which enables a recording paper to be easily removed when it is jammed in a conveying path, and which can record an image on a recording paper in good condition and obtain a high quality image.
In the image forming apparatus of the present invention, when a cover is closed, a transcribing device can be provided at a suitable position relative to a photosensitive member, and a pair of register rollers can be provided in suitable condition.
The present invention may provide an image forming apparatus comprising: an apparatus main body with an opening portion; a cover provided on the apparatus main body, the cover being movable between a sealing position where the opening portion is covered, and an exposing position where the opening portion is uncovered; an image forming unit provided in the apparatus main body and including a photosensitive member on which a toner image is formed; a transcribing device provided in the apparatus main body and transferring the toner image on the photosensitive member onto a recording paper; a fixing device provided on the cover and fixing the toner image on the recording paper; a register roller provided in the apparatus main body and conveying the recording paper to the photosensitive member; and a discharging mechanism disposed in the apparatus main body, conveying the recording paper on which the toner image has been fixed, and discharging the recording paper to the outside of the apparatus main body.
The invention may provide an image forming apparatus comprising: an apparatus main body with an opening portion; a cover provided on the apparatus main body, the cover being movable between a sealing position where the opening portion is covered, and an exposing position where the opening portion is uncovered; an image forming unit provided in the apparatus main body and including a photosensitive member on which a toner image is formed; a transcribing device provided in the apparatus main body and transferring the toner image on the photosensitive member onto a recording paper; a fixing device provided on the cover and fixing the toner image on the recording paper; a register roller provided in the apparatus main body and conveying the recording paper to the photosensitive member; a discharging mechanism provided on the cover, conveying the recording paper on which the toner image has been fixed, discharging the recording paper to the outside of the apparatus main body; and conveying reversely the recording paper toward the cover at the time of double-side recording; and a reverse conveying mechanism provided on the cover and conveying the recording paper, which has been reversely conveyed by the discharging mechanism, toward the register roller.
The invention may provide an image forming apparatus comprising: an apparatus main body with an opening portion; a cover provided on the apparatus main body, the cover being movable between a sealing position where the opening portion is covered, and an exposed position where the opening portion is uncovered; an image forming unit provided in the apparatus main body and including a photosensitive member on which a toner image is formed; a transcribing device provided in the apparatus main body and transferring the toner image on the photosensitive member onto a recording paper; a fixing device provided on the cover and fixing the toner image on the recording paper; a register roller provided in the apparatus main body and conveying the recording paper to the photosensitive member; a discharging mechanism provided on the cover, conveying the recording paper on which the toner image has been fixed by the fixing device, and discharging the recording paper to the outside of the apparatus main body; a manual feeding roller provided in the apparatus main body; and a manual feeding guide provided in the apparatus main body.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.